"Any questions you have for me, write backwards and offer to your editors as think-pieces. Just ask your editors to label such fanciful essays as 'Analysis'." So announces the former newsman turned adviser, Irwin Maurice Fletcher when the press corps is gathered in Fletch and the Man Who (1983). One of the most entertaining novels about a Presidential campaign, it found Fletch caught up in as much louche behaviour – including murder – as any of those in which Gregory Mcdonald featured him. After a 1974 debut, these took their Boston author from near-destitution to worldwide sales and films with Chevy Chase – all of which made him seek sanctuary on a Tennessee farm.

The son of a writer and broadcaster, Irving, and a painter, Mae, Mcdonald was born in 1937 in Shrewsbury, Massachusetts. His diverse interests were apparent at Harvard, where he paid his way with sailing lessons while writing a novel told from the point of view of a WASP student who – very Camus – coolly watched his jazz-loving room-mate commit suicide and then took up with the sister. This was published in 1964.

By then Mcdonald had, after graduating in 1958, been a marine underwriter and sailed the world as well as running a service which rescued well-heeled novice yachtsmen from choppy waters; a year with the Peace Corps was followed by high school teaching before his palpable relish of life prompted The Boston Globe to offer him a freewheeling column in which John Wayne was as likely to appear as Andy Warhol.

High-energy stuff, it left him jaded after a decade. He hankered to write novels, and was encouraged to quit the paper by his wife, Susie, whom he had married in 1963. He was soon broke, but $10,000 from Paramount for Running Scared bought time for Fletch (1974). Publishers had been wary of Mcdonald after that first novel, which did not balk at putting a puppy out of its misery after a car accident ("he squeezed harder, using both hands, feeling the windpipe like a thin, rubbery cord betwen the fingers").

Where that character, Tom Betancourt, was a control freak, Fletch was an easy-going reporter, investigating seaside drug-dealing while disguised as a beach-bum, who is offered $20,000 by one Alan Stanwyck to murder him. This is an insurance scam, Stanwyck suffering virulent cancer, and his wife unable to benefit should he commit suicide. It is not as simple as that. Having accepted the offer after upping it, Fletch finds that Stanwyck had married into Collins Aviation (the wife is called Joan). What's more, the police chief is running a racket. All of which leads to Fletch filing a great beach story before reversing a double-cross – and leaving for Rio with $3m in untraceable notes.

That was meant to be that. If Mcdonald's earlier portrayal of immorality had been too disturbing for many, this comic variant upon it brought a clamour for more. These followed at a clip, some volumes going back in time, while another, Confess, Fletch (1976), found him using his wealth in fine-art circles and on the point of another marriage when accused of murder by a detective, the cello-playing Francis Xavier Flynn, who was then given three novels to himself. These lack the zest of the Fletch titles, which move between such milieux as film-making, the law, politics and Rio de Janeiro.

Plots overlap, sustaining such dialogue as "politics is advantageous loyalty, son" and their worldview is encapsulated in: "Society changes, Fletcher, but not much. It doesn't die. It moves. It oozes. It changes its shape, its structure, its leaders and its entertainments. There is always a Society. As long as the instinct for power beats in the breasts of men and women, there will be a restricted clawing called Society."

With a mid-Eighties move to a Tennessee cattle farm, Mcdonald sought retreat and, amid divorce, also wound down the series. He became involved in local life, not least in taking steps to prevent a resurgence of the Klan. He created two novels around the Southern figure of Skylar, and reprised Fletch with the arrival of his son Jack, conceived during a fling in a shower. Among other, one-off titles were Safekeeping (1985) and a ransom thriller Who Took Toby Rinaldi? (1980), but not yet published in England is his Time Squared series, about the onset of middle age, and a collection of his Globe work.